Fortran 95 source code to compute the Fibonacci-series.

fibonacci.f95

!****************************************************
! フィボナッチ数列計算
!
!   DATE        AUTHOR       VERSION
!   2018.08.20  mk-mode.com  1.00 新規作成
!   2021.12.07  mk-mode.com  1.01 recursive を削除
!
! Copyright(C) 2018-2021 mk-mode.com All Rights Reserved.
!****************************************************
!
program fibonacci_main
  implicit none

  print *, fibonacci(0, 1, 20)

  stop
contains
  ! フィボナッチ数列の計算
  ! * 初項 f1, f2, 長さ n のフィボナッチ数列を返す
  !
  ! :param(in) integer f1
  ! :param(in) integer f2
  ! :param(in) integer n
  ! :return    integer fibonacci(1:n)
  function fibonacci(f1, f2, n)
    implicit none
    integer, intent(in) :: f1, f2, n
    integer :: fibonacci(1:n)
    integer :: i

    fibonacci(1) = f1
    fibonacci(2) = f2

    do i = 3, n
      fibonacci(i) = fibonacci(i - 1) + fibonacci(i - 2)
    end do
  end function fibonacci
end program fibonacci_main

Hi, thank you for your example. I have a question. In my opinion, this is an iterative version. You return the array with the same name as a function. If you remove the recursive keyword, the function still works. In other words, the fibonacci(i) is an array call... not a recursive function call.

Thank you for letting me know.
I don't remember clearly because it was a long time ago.
But certainly "recursive" wasn't needed.
I removed "recursive".